In an optical disk drive apparatus, when the amplitude or the offset value of a Tracking Error Signal (TES) indicates a positional deviation of an optical head from a track on an optical disk, or a Focusing Error Signal (FES) indicates a deflection from a focusing state of a beam of light is corrected, the optical head may be stopped. The expression "the optical head may be stopped" as used herein does not mean that a pickup head remains put down in a certain track on the optical disk, but means that the pickup head is stopped at an absolute position in the radial direction of the optical disk. The TES is therefore generated if the optical disk rotates while the optical head stops since the optical disk and a drive apparatus to which the optical disk itself is attached, in a strict sense, are not co-axial.
The conventional optical disk apparatus may be provided with a dedicated sensor for detecting an absolute position of the optical head in the radial direction of the optical disk and controlled to stop the optical head based on a value read by the dedicated sensor. However, a problem exists in that the dedicated sensor causes the number of parts to be increased and prevents the making of a small-sized apparatus. Such a problem would occur also for the fixing of the optical head by providing means for fixing the head such as a mechanical latch mechanism, etc.